At operating devices for doors, gates and such elements, it is common to use electrohydraulic systems. If the operating device is to manage pivot operation, it is more common with an electromechanic system. Irrespective of the choice of system, problems arise when a operating device is to be mounted at an already existing operable element. The space available at, e.g., a door is a limiting factor. This may cause expensive alteration costs in order to modify the space. At production of new houses, the cost also increases when operating devices occupy space.
With the classification operating device for elements is referred to devices that cause doors, gates and such to move either linearly or to pivot. The devices permit left hung or right hung elements, outer elements or inner elements and the devices may be placed on optional side of the element.
The patent specification GB 1 406 126 shows an electrohydraulic door opener and the object of the invention is to make a space-saving and handy device. The door opener comprises a combination of a hydraulic motor, a hydraulic fluid tank, a motor driven hydraulic pump and hydraulic lines, which together form a closed hydraulic circuit/loop. A rotating motor drives or operates the pump. In order to save space, a spring housing 14 is also utilized as a hydraulic fluid tank.
The patent specification U.S. Pat. No. 4,333,270 shows an electromechanic door opener. The object of the invention is to make a door opener, which is cheap to manufacture and which fits for different types of pivoting doors. Furthermore, the object is to make a door opener that, among other thing, has a long service life. The solution is based on a construction that, among other things, contains a rack and a gear-wheel. It does not contain any hydraulics.
Problems arise when the operating device should be inexpensive to manufacture and to operate and quiet. The electrohydraulic systems contain numerous and expensive components and are thereby expensive to manufacture. Installed electrohydraulic systems are energy-demanding and thereby expensive to operate. Also electromechanical systems contain many expensive components and are thereby also expensive to manufacture. Installed electromechanical systems are expensive to operate because of the high energy-demanding friction always inherent in mechanical constructions. Hydraulic pumps as well as mechanical transmissions generate noise that in the long run may be perceived as disturbing.
On production of operating devices of the above-mentioned type, the need thereby arises to manufacture devices consisting of a few inexpensive components and which devices, ready-made and mounted, are silent and inexpensive to operate. The operating device should be a small, compact constructional solution, which does not demand any large mounting space.
None of the operating devices, which are shown in the stated patent specifications, can meet this need.